Speaking exclusively to the Weekend Herald, Gattung said it would be after Easter before some test results came back.
"This is a bit of a lesson in patience for me - which is quite hard."
Gattung described herself as the "eldest daughter of immigrant parents with a mind that never stops and a Catholic 'responsibility' gene".
But last week, sitting in a modern wingback chair overlooking the lap pool at her Westmere, Auckland home, she said she had to take notice of what her body was telling her. "As I left the hospital, the last thing the registrar said to me was 'take it easy' - and I didn't say 'that's a Tui billboard'.
"Do I want to keep going at the pace I've gone at since I was 15? I'm the crazy woman who did extra subjects for School Cert. What was that about?"
In 2006, Forbes placed Gattung at number 49 in a list of the world's Top 100 Most Powerful Women. She chairs insurance group AIA Australia, Wellington SPCA, Telco Technology Services, Co.OfWomen (which supports female entrepreneurship) and luxury beauty distributor The Six Senses, and is a director on a number of other boards.
A long-time Wellington resident, Gattung this week confirmed the sale of her $2.8m Oriental Parade apartment for an undisclosed sum. She told the Weekend Herald she would miss the view ("it's a grand vista – it makes me think that's everything's possible) but her family were centred around Auckland and Waihi Beach (where she also has a property). "It's a little bit about simplifying my life, really."
Her current work focus is the launch of SheEO New Zealand, a scheme seeking 500 women to make an $1100 act of "radical generosity" that will be split as interest free loans between five female-led ventures. Gattung said 370 activators had already signed up (she is hoping for 500 by Easter) and the successful businesses and social enterprises would be announced at a gala summit in Auckland on April 9.
"We've heard a lot about the Me Too movement. I consider this an 'Us Too' moment. It's as hard for women to get early stage venture capital funding in New Zealand as it is anywhere else in the world.
"How else do we birth some of these new initiatives that actually can make a huge difference if we don't collectively activate the fact that women are half the world? We're not the minority."
Gattung said she had been extremely well supported by her female network since her collapse, which she describes as a faint not a seizure.
"It could have been a virus. I'd only just got back from several weeks in South America. I'm cool about the fact that we may never know what caused it."
In recent weeks, she has had two further episodes of waking up to the room spinning but had not been re-hospitalised and was being treated for Benign Paroxysmal Positional Vertigo, a condition created when tiny deposits of calcium in the inner ear canal end up in the wrong position.
Gattung has spoken previously about an interest in complementary medicine. This week, she said "Western medicine is tremendous in a crisis, of course!"
She was, however, practising mindfulness exercises in line with instructions to rest and slow down.
"I'm trying to ground myself and stay in the present and not go 'oh, I need to be doing this, this week'."
And, she said, "I can't say enough about the therapeutic impact of stroking my cats!"
Gattung said she was an optimist by nature.
"This was a sudden interruption in my normal routine but I haven't, in the last couple of weeks, thought 'this is it'."